Delustered artificial silk and method of delustering



Patented den. 6%, i932 WILLIAM H. LOBIMIEE, F CLEVELAND, DECK)DELUSTEEED ARTEIGIAL $111K AND METHOD OF DELUSTERING lilo Drawing.

This invention relates to the art of delustering artificial silk orrayon and to the re sulting product.

Artificial silk, unless delustered during its manufacture into threads,possesses a high sheen or luster which is in marked contrast to that ofnatural silk. Efforts have been made heretofore to alterthis appearanceso as to give the artificial silk an appearance w more closelyresembling natural silk. So far as I am aware such efiorts have not beencommercially satisfactory.

l have devised a method of delustering artificial silk, however, whichgives a high- 35 ly desirable product with any desired degree of luster,can be quickly,eas1ly and inexpensively employed and possesses. theadditional virtue that by its use before the artificial silk is dyed,the amount of dyestufi otherwise rem quired for a desired shade or depthof color can be materially decreased. 1

The present method may be practiced on artificial silk in the form ofthread, bank or skein, or piece goods. It may be carried out before orduring dyeing, and after dyeing in the-case of certain dyes which arenot dissolved or otherwise harmfully effected by the substances employedfor delustering. My-invention is based'on the discovery that go whenartificial silk or rayon is suitably brought into contact with a liquidto which has been added certain inorganic salts which react to form anextremely fine, extremely insoluble precipitate, the artificial silk orrayon is delustered in proportion to the amount of salts used, itsstrength and softness as present in the finished product are preservedsubstantially unimpaired and the delustering is permanent under theordinary to subsequent processing operations and the ordinary serviceconditions.

As an illustration of my invention and of substances having suitableproperties I give the following detailed description:

Alum and barium chloride in the desired amounts are dissolved in hotwater and added to a bath. Then the artificial silk is immersed thereinunder proper temperature conditions and for a length of time sufficientto for the delnstering action to take place; I

Application filed January 21, 1929. Serial K0. 334,127.

prefer to use approximately equal parts of the two above mentionedsalts. For nearly complete delustering about one percent of each salt(based on the weight of artificial silk to be treated) has been foundsatisfactory but the amounts may be increased severalpercent I withslight additional delustering. For only partial delustering thepercentage of salts may be decreased so that only a small fraction ofone percent of each salt is present, the degree of delustering varyingwith the amount of salts used.

I have found that when the delusterin'g and dyeing are carried out inthat order the amount of dyestulf required for a given shade or colorcan be decreased perhaps fifteen per about. 70 F. to about 212 F. but,since artificial silk tends to become somewhat brittle and to losestrength when heated near the boiling point of water, I prefer not toexceed about 180 F. Very good results can be obtained at temperaturesfrom about 70 F. and about 180 F. and particularly g5 between about F.and about F The delustering action takes place quickly where theartificial silk is in such form thatthe threads can bebrought properlyand quickly into the solution, as in the case of a single thread, andsomewhat more slowl as The product resulting from this method has anappearance more or less resembling that of natural silk, and itsstrength and softness is substantially unimpaired.

When artificial silk is treated as aforesaid some action takes place,which may be due to 'a chemical phenomenon, by which there is in thecase of a skein or woven piece w ere the skein or piece or the solutionis agitated .to bring about the proper contact.

brought about such a combination between the artificial silk and certainsubstances in the solution that the desired delustering is accomplished.

Having thus described my invention in sufiicient detail for thoseskilled in the art to understand and practice the same, what I desire tosecure by Letters Patent is defined in what is claimed:

1. The method of delustering artificial silk which comprises providingasolution containing approximately equal parts of alum and bariumchloride totalling from a fraction of one percent up to about fivepercent by weight of the silk, and bringing the silk into suitablecontact with the solution while maintaining the temperature of thesolution between about 70 F. and 212 F.

2. The method of delustering artificial silk which comprises immersingthe silk in a solution heated between about 160 F. and about 180 Randcontaining approximately equal parts of alum and barium chloridetotalling between a fraction of one percent and five percent by weightof the silk and bringing the silk into the solution in a manner topermit uniform delustering of-the silk.

3. The method of delustering artificial silk which comprises providing asolution heated between about 160 F. and about 180 F. and containingapproximately equal parts of alum and barium chloride totalling betweenabout one and about three percent by weight of the silk, and bringingthe silk into contact therewith in a manner to permit uniformdelus'tering of the silk.

45. The method of delustering artificial silk which comprises immersingthe silk in a solution heated between about 7 0 F. and about 212 F. andcontaining approximately equal parts ofalum and barium chloridetotalling between a fraction of one percent and three percent by weightof the silk, and bringing I the silk into the solution in a manner topermit uniform delustering of the silk.

5. The method of delusterlng artificial silk which comprises providing asolution heated between about F. and about F. and containingapproximately equal parts of alum and barium chloride totalling abouttwo percent by weight of the silk,'and bringmg the silk into contacttherewith in a manner to permit uniform delustering of the silk.

6. The method of delnstering artificial silk which comprisesimmersingthe silk in a solution heated between about 7 0 F. and 212 F.and containing approximately equal parts of alum and barium chloridetotalling about two percent by weight of the silk, and bringing the silkinto the solution in a manner to permit uniform delustering of the silk.

In testimony whereof I hereunto aifix my signature this 17th day ofJanuary, 1929.

WILLIAM H. LORIMER.

ea ers

